Method and system for identifying and displaying groups of cardiac arrhythmic episodes

ABSTRACT

A medical device system that receives cardiac data representing a plurality of stored arrhythmic episodes, and analyzing the cardiac data to identify and display a subset of stored arrhythmic episodes as a function of user-specified episode criteria. The medical device system presents a query window on an interactive display in order to receive user-specified episode criteria via one or more input fields. The medical device displays only those episodes matching the episode criteria such as arrhythmia type, zone of detection, date of occurrence and average heart rate in beats per minute (BPM).

CROSS REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. patent application Ser. No.10/118,537, filed on Apr. 8, 2002, now issued as U.S. Pat. No.6,843,801, which is continuation of U.S. patent application Ser. No.09/378,406, filed on Aug. 20, 1999, now issued as U.S. Pat. No.6,418,340, the specification of which is incorporated herein byreference.

TECHNICAL FIELD

The present invention relates generally to medical devices and inparticular to a system of analyzing cardiac data to identify and displaygroups of cardiac arrhythmic episodes.

BACKGROUND OF INVENTION

Implantable cardiac defibrillators (ICDs) are well establishedtherapeutic devices for treating patients who have experienced one ormore documented episodes of hemodynamically significant ventriculartachycardia or ventricular fibrillation. Since their clinical inceptionmore than two decades ago, ICDs have evolved from basic to sophisticatedelectronic devices that provide physicians with a variety of clinicallyuseful functions with which to treat patients.

Presently, even the most basic of ICDs typically has more than onetachycardia detection criterion, tiered therapy which combinesbradycardia support pacing with various antitachycardia pacing modes,low-energy cardioversion, defibrillation, and data logging capabilities.The data logging capabilities within ICDs have become increasinglyimportant, since the amount of data required for the ICDs operationincreases proportionally with the increase in ICD functions. Efficientlyprocessing this large amount of data has become possible with theincorporation of microprocessors and memory within the ICD.

Even with the advances in ICD data logging and processing capabilities,arrhythmia event recording capabilities have been limited, making itdifficult to verify the adequacy and efficacy of arrhythmia detectionand therapy settings. Furthermore, ICDs have been designed to recordelectrocardiogram and diagnostic channel data which can indicate to thephysician the ICDs behavior during multiple tachyarrhythmic episodes.These ICDs also include arrhythmic event counters which log the numberof episodes detected and the success or failure of each programmedtherapy. Moreover, monitoring capability in some ICDs allow forrecording of electrocardiogram waveforms, which can assist the physicianin assessing the efficacy of the implanted ICD.

Once an ICD has been implanted, the physician interacts with the ICDthrough a clinical programmer. The clinical programmer is used toestablish a telemetric link with the implanted ICD. The telemetric linkallows for instructions to be sent to the electronic circuitry of theICD and clinical data regarding the occurrence and treatment of apatient's cardiac arrhythmias and the ICD's operation to be sent fromthe electronic circuitry of the ICD to the clinical programmer. Thetypical programmer is a microprocessor-based unit that has a wand forcreating the telemetric link between the implanted ICD and theprogrammer, and a graphics display screen that presents a patient'srecorded cardiac data and ICD system information to the physician.

As the amount of cardiac data recorded by ICDs increases with each newgeneration of ICD, manufacturers and clinicians alike are becoming moresensitive to the role that time-efficient programming and datainterpretation plays in the physician's clinical visit with the patient.As ICDs become increasingly complex, the interpretation of recordedarrhythmic episodes and the programming of the ICD can be challengingand time-consuming tasks for some users.

Therefore, a need exists for improved ICD and programmer technology thatfacilitates the identification of relevant information regarding thepatient's clinical status. There is a need in the art for a system thatfacilitates the quick identification and presentation of groups ofarrhythmic episodes within ICD recorded arrhythmic data.

SUMMARY OF THE INVENTION

The present disclosure describes a medical device system for analyzingcardiac data in order to identify and display groups of arrhythmicepisodes. In one embodiment, the invention is directed toward a methodof receiving the cardiac data representing a plurality of storedarrhythmic episodes, analyzing the cardiac data to identify a subset ofstored arrhythmic episodes as a function of user-specified criteria, anddisplaying the subsets to an interactive screen of a medical deviceprogrammer.

According to the invention, only those episodes having characteristicsthat match the user-specified criteria are displayed. The criteria canbe, but is not limited to, an arrhythmia type, a zone of detection, adate of occurrence and an average heart rate in beats per minute (BPM).By analyzing the cardiac data and only displaying the patient's recordedcardiac arrhythmic episodes of interest, the physician can more quicklyassess and interpret the nature of the patient's cardiac arrhythmias andprovide for more effective and efficient programming of the patient'sICD.

In another embodiment, the medical device system that comprises acardiac defibrillator and a medical device programmer unit for thecardiac defibrillator. The cardiac defibrillator includes electroniccontrol circuitry for determining and recording the occurrence ofarrhythmic episodes of a heart. The programmer unit has programmerelectronic circuitry that is coupled to an interactive display screenand which receives cardiac data representing a plurality of storedarrhythmic episodes from the electronic control circuitry. Theprogrammer electronic circuitry analyzes the cardiac data to identifyand displays a subset of stored arrhythmic episodes as a function of theuser-specified criteria.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, where like numerals describe like components throughoutthe several views:

FIG. 1 is an embodiment of an implantable cardiac defibrillatorimplanted into a heart of a patient, from which portions have beenremoved to show detail;

FIG. 2 is a block diagram of an implantable cardiac defibrillatoraccording to one embodiment of the present invention;

FIG. 3 is a perspective view of an external programming unit, accordingto one embodiment of the present invention, which is used forcommunicating with the implantable cardiac defibrillator of FIG. 1;

FIG. 4 is a flow diagram illustrating one mode of operation of animplantable cardiac defibrillator and a medical device programming unitincorporating the present invention;

FIG. 5 illustrates a display screen presenting one embodiment of asummary widow that, according to the invention, displays a set ofarrhythmic episodes that are selected according to episode criteriaspecified by the user; and

FIG. 6 illustrates the display screen presenting one embodiment of aquery input widow that contains a variety of pull down windows and otherinput fields by which a user enters criteria in order to identify andview a subset of the arrhythmic episodes received from cardiacdefibrillator.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings which form a part hereof and in which is shown byway of illustration specific embodiments in which the invention may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice and use the invention, andit is to be understood that other embodiments may be utilized and thatelectrical, programmatic, and structural changes may be made withoutdeparting from the spirit and scope of the present invention. Thefollowing detailed description is, therefore, not to be taken in alimiting sense and the scope of the present invention is defined by theappended claims and their equivalents.

The embodiments of the present invention illustrated herein aredescribed as being included in an implantable cardiac defibrillator,which may include numerous pacing modes known in the art, and anexternal medical device programmer. However, the medical system andmethod of the present invention could also be implemented in an externalcardioverter/monitor system as are known in the art. Also, the medicalsystem and method of the present invention could also be implemented inan implantable atrial cardioverter-defibrillator, which may includenumerous pacing modes known in the art. Furthermore, although thepresent invention is described in conjunction with an implantabledefibrillator having a microprocessor based architecture, it will beunderstood that the implantable cardiac defibrillator (or otherimplanted device) may be implemented in any logic based, customintegrated circuit architecture, if desired.

Referring now to FIG. 1 of the drawings, there is shown one embodimentof a medical device system which includes an implantable cardiacdefibrillator 20 electrically and physically coupled to at least oneintracardiac catheter 22. In one embodiment, the intracardiac catheter22 includes one or more pacing electrodes and one or more intracardiacdefibrillation electrodes.

The intracardiac catheter 22 is implanted in a human body 24 withportions of the intracardiac catheter 22 inserted into a heart 26 todetect and analyze electric cardiac signals produced by the heart 26 andto provide electrical energy to the heart 26 under certain predeterminedconditions to treat cardia arrhythmias, including ventricularfibrillation, of the heart 26.

In one embodiment, the intracardiac catheter 22 is an endocardial leadadapted to be releasably attached to the cardiac defibrillator 20. Theintracardiac catheter 22 has an elongate body with a proximal end 28 anda distal end 30 and is shown as having a pacing electrode 32 located at,or adjacent, the distal end 30 of the intracardiac catheter 22. In oneembodiment, the pacing electrode 32 is a tip electrode positioned at thedistal end 30 of the intracardiac catheter 22. Alternatively, the pacingelectrode 32 is an annular, or a semi-annular ring electrode positionedadjacent the distal end 30.

The intracardiac catheter 22 also includes one or more defibrillationelectrodes. In one embodiment, the intracardiac catheter 22 has a firstdefibrillation electrode 34 and a second defibrillation electrode 36,where the first defibrillation electrode 34 and the seconddefibrillation electrode 36 are defibrillation coil electrodes as areknown in the art. The first defibrillation electrode 34 is spaced apartand proximal from the pacing electrode 32, and the second defibrillationelectrode 36 is spaced apart and proximal from the first defibrillationelectrode 34 such that when the intracardiac catheter 22 is positionedwithin the heart 26 the pacing electrode 32 and the first defibrillationelectrode 34 reside within a right ventricle 38 of the heart 26, withthe pacing electrode 32 in an apex location within the right ventricle38, and the second defibrillation electrode 36 is positioned within theright atrium chamber 40 of the heart 26 or a major vein leading to theright atrium chamber 40 of the heart 26.

Referring now to FIG. 2, there is shown an embodiment of a block diagramof a cardiac defibrillator 20. The cardiac defibrillator 20 includeselectronic control circuitry 42 for receiving cardiac signals from aheart 26 and delivering electrical energy to the heart 26. Theelectronic control circuitry 42 includes terminals, labeled withreference numbers 44, 46, and 48 for connection to electrodes attachedto the surface of the intracardiac catheter 22. The pacing electrode 32is electrically connected to terminal 44 and to the electronic controlcircuitry 42 through an electrically insulated conductor provided withinthe elongate body of the intracardiac catheter 22. The firstdefibrillation electrode 34 and the second defibrillation electrode 36are connected to terminals 46 and 48, respectively, and to theelectronic control circuitry 42 through electrically insulatedconductors provided within the elongate body of the intracardiaccatheter 22.

In one embodiment, the electronic control circuitry 42 of the cardiacdefibrillator 20 is encased and hermetically sealed in a housing 50suitable for implanting in a human body. In one embodiment, titanium isused for the housing 50, however, other biocompatible housing materialsas are known in the art may be used. A connector block 52 isadditionally attached to the housing 50 of the cardiac defibrillator 20to allow for the physical and the electrical attachment of theintracardiac catheter 22 and the electrodes to the cardiac defibrillator20 and the encased electronic control circuitry 42.

The electronic control circuitry 42 of the cardiac defibrillator 20 is aprogrammable microprocessor-based system, with a microprocessor 54 and amemory circuit 56, which contains parameters for various pacing andsensing modes and stores data indicative of cardiac signals received bythe electronic control circuitry 42.

A transmitter circuit 58 is additionally coupled to the electroniccontrol circuitry 42 and the memory circuit 56 to allow the cardiacdefibrillator 20 to communicate with a programmer unit 60. In oneembodiment, the transmitter circuit 58 and the programmer unit 60 use awire loop antenna 62 and a radio frequency telemetric link, as is knownin the art, to receive and transmit signals and data to and from theprogrammer unit 60 and the electronic control circuitry 42. In thismanner, programming commands or instructions are transferred to themicroprocessor 54 of the cardiac defibrillator 20 after implant, andstored cardiac data pertaining to sensed arrhythmic episodes within theheart 26 and subsequent therapy, or therapies, applied to correct thesensed arrhythmic event are transferred to the programmer unit 60 fromthe cardiac defibrillator 20.

The embodiment of the cardiac defibrillator block diagram shows thepacing electrode 32 coupled to a sense amplifier 64. In an additionalembodiment, the housing 50 of the cardiac defibrillator 20 is alsocoupled to the sense amplified 64 at 65 to allow for unipolar cardiacrate sensing between the pacing electrode 32 and the housing 50 of thecardiac defibrillator 20. The output of the sense amplifier 64 is shownconnected to an R-wave detector 66. These components serve to sense andamplify the QRS waves of the heart, and apply signals indicative thereofto the microprocessor 54. Among other things, microprocessor 54 respondsto the R-wave detector 66 by providing pacing signals to a pace outputcircuit 68, as needed according to the programmed pacing mode. Paceoutput circuit 68 provides output pacing signals to terminals 44 and 65,which connect to the pacing electrode 32 and the housing 50 of thecardiac defibrillator 20, for cardiac pacing.

The first defibrillation electrode 34 and the second defibrillationelectrode 36 are coupled to a sense amplifier 70, whose output isconnected to a cardiac morphology detector 72. These components serve tosense and amplify the QRS-waves of the cardiac cycle from theventricular region of the heart 26, and apply signals indicative thereofto the microprocessor 54. In one embodiment, the cardiac morphologydetector 72 includes an analog filter for filtering cardiac signal noisesensed by the electrodes. The cardiac signals are then bandlimitedbefore arriving at an analog-to-digital filter. The cardiac signals arethen A/D converted into a digital signal and subsequently received bythe microprocessor 54. In an alternative embodiment, the cardiac signalsare filtered through an analog peak detector to extract the maximum andminimum cardiac signal values for each sensed cardiac interval.

The microprocessor 54 responds to the cardiac signals sensed within theheart 26 using the intracardiac catheter 22 by providing signals tocardioversion/defibrillation output circuitry 74 to provide eithercardioversion or defibrillation electrical energy to the heart 26depending upon nature of the arrhythmia sensed by the cardiacdefibrillator 20. Power to the cardiac defibrillator 20 is supplied byan electrochemical battery 76 that is housed within the cardiacdefibrillator 20.

For each arrhythmic episode sensed, cardiac defibrillator 20 storesepisode data in memory circuit 56 as illustrated in Table 1. Otherarrhythmic episode data known in the art can also be recorded and storedin the memory circuit 56.

TABLE 1 STORED DATA DESCRIPTION Number Episode number stored inchronological order. Time stamp Date and time of the episode. Type Thetype of episode detected such as spontaneous, induced,pacemaker-mediated tachycardia (PMT), atrial tachyarrhythmia response(ATR) or magnet activated. Zone The zone of detection which can be (VF),(VT), VT-1, Commanded, and Accelerated. Rate The average rate of theepisode in beats per minute. Therapy Therapy that was delivered to thepatient prior to detection including: none, one ATP, more than one ATP,one shock, more than one shock, ATP and shock. Enhancement Any detectionenhancement criteria. R-R Intervals The time intervals betweenconsecutively sensed R-waves for the episode. EGMs Data representing thesensed electrocardiogram signal such as a ventricular signal and anatrial signal. Duration The duration of the episode.

Referring now to FIG. 3, there is shown one embodiment of a medicaldevice programmer 60 of the medical device system. As previouslymentioned, one embodiment of programmer 60 for the implantable cardiacdefibrillator 20 takes the form of an external controller as are knownin the art. However, in an alternative embodiment, the medical devicesystem is a completely external device such as an externalcardioverting/defibrillator system as are known in the art, where theprogrammer unit is physically and electronically integrated intoelectronic control circuitry similar to the electronic control circuitry42 of the cardiac defibrillator 20. An example of this latter embodimentis for an external cardiac monitor and defibrillation unit, electricallyconnected to the heart by any combination of intracardiac catheters,epicardial electrodes and/or externally cardiac electrodes, all of whichare known in the art.

FIG. 3 shows one embodiment of programmer 60 designed to be positionedexternal of the human body 24 for communicating with an implantablemedical device, such as the cardiac defibrillator 20 from FIG. 1, via RFtelemetry. Programmer 60 has programmer electronic circuitry, includinga microprocessing unit and related circuitry, such as digital memory,which is coupled to a graphics display screen 102.

In one embodiment, programmer 60 comprises an outer housing 100 which ismade of a thermal plastic or other suitable lightweight durablematerial. The graphics display screen 102 is disposed on the uppersurface of housing 100. The graphics display screen 102 folds down intoa closed position when programmer 60 is not in use, thereby reducing thesize of programmer 60 and protecting the display surface of graphicsdisplay screen 102 during transportation and storage.

In an additional embodiment, the external programmer additionally has afloppy disk drive and a hard drive disposed within the housing. Airvents are provided at various points in the housing 100 so that aninternal fan can circulate air within the housing 100 and preventoverheating of components therein.

Programmer 60 is shown with the graphics display screen 102 positionedin one of a plurality of possible open positions such that a display onthe graphics display screen 102 is visible to a user situated in frontof programmer 60. In one embodiment, the graphics display screen 102 isof a liquid crystal display (LCD). The graphics display screen 102 isoperatively coupled to the electronic circuitry disposed with thehousing 100 and is adapted to provide a visual display of graphicsand/or data under control of the programmer electronic circuitry.

Programmer 60 further includes a user input device coupled to theelectronic circuitry. In one embodiment, the user input device is thegraphics display screen 102, which is provided with touch-sensitivecapability, such that a user can interact with the programmer electroniccircuitry by touching the display area on the graphics display screen102 with a stylus 104, or even the user's finger. In one embodiment, thetouch-sensitive graphics display screen is primary input for programmer60. Programmer 60 further includes a programming head 106, which isplace over a patient's body near the implant site of an implanteddevice, such as the cardiac defibrillator 20, in order to establish atelemetry link between the cardiac defibrillator 20 and programmer 60.The telemetry link between the cardiac defibrillator 20 and programmer60 allows the electronic circuitry coupled to the graphics displayscreen to be coupled to the electronic control circuitry of the cardiacdefibrillator 20. The programming head 106 is coupled to the electroniccircuitry of programmer 60 and a receiver circuit for receiving signalsfrom the transmitter circuit indicative of cardiac signals by a cable108.

The stylus 104 used to interact with the touch-sensitive graphicsdisplay screen 102 is coupled to the programmer electronic circuitrywithin the housing 100 by a cable 110. Alternatively, programmer 60 maybe equipped with a conventional computer “mouse”-type pointing device,rather than a stylus. In the absence of either a stylus or a mouse,on-screen cursor control for enabling user interaction with programmer60 may be facilitated through cursor control keys 112 (arrow keys or thelike) disposed on programmer 60.

Programmer 60 further includes a receiver circuit for receiving signalsfrom the transmitter circuit indicative of cardiac signals. Through thetelemetric contact with the cardiac defibrillator 20, programmer 60 iscapable of capturing and storing recorded electrocardiogram datatransmitted from the cardiac defibrillator 20 and displaying theelectrocardiogram data on its graphics display screen 102.

FIG. 4 illustrates a flow diagram of one mode of operation of cardiacdefibrillator 20 and programmer 60 according to the present invention.Process 400 begins at block 402 and proceeds to block 404 where cardiacdefibrillator 20 senses signals representing arrhythmic episodesexperienced by a patient and provides therapy for the sensed arrhythmicepisodes. Cardiac defibrillator 20 electronically records cardiac datacorresponding to the sensed arrhythmic episodes in memory 56. Such dataincludes an episode number, a type, etc. as described in Table 1 above.At block 406 programmer 60 interrogates the implanted cardiacdefibrillator 20. During the interrogation, the stored data istransferred from the electronic control circuitry 42 and received byprogrammer 60.

After receiving the stored cardiac data from the cardiac defibrillator20, programmer 60 displays a high-level summary of the recordedarrhythmic events in a spreadsheet-like format. This is typically achronological textual list of a plurality of arrhythmic events recordedby the cardiac defibrillator 20. The summary of the recorded arrhythmicevents displays the data described in Table 1 above such as achronological number of the episode, the date and time of the episode,the type of episode detected, the onset rate of the episode, thestability of the episode, the duration of the episode, the average ratein beats per minute, and the type of therapy delivered.

In conventional systems, a user would need to manually scan throughmultiple episodes in order to identify and view relevant information.Programmer 60, however, provides a more convenient and more accessibleway of identifying, viewing, and analyzing arrhythmic episodes ofinterest.

For example, in block 408 programmer 60 presents on display screen 102one or more episode criteria inputs by which a user can input criteriain order to view a subset of the arrhythmic episodes received fromcardiac defibrillator 20. In one embodiment programmer 60 presents sixdata filters that can be modified by the user as detailed in Table 2below.

TABLE 2 EPISODE CRITERIA DESCRIPTION AND VALID PARAMETERS OccurrenceAnalyze data and identify episodes based on date of Date occurrence.Valid parameters include: all episodes, episodes that occurred sincecardiac defibrillator 20 was last reset, and episodes falling with aspecified range of dates. Episode Analyze data and identify episodesbased on episode type. Type Valid parameters include: All, Spontaneous,Induced, PMT (pacemaker-mediated tachycardia), ATR (atrialtachyarrhythmia response) and Magnet (magnet induced). Zone Analyze dataand identify episodes the zone of detection which can be VF (ventricularfibrillation), VT (ventricular tachycardia), VT-1 (ventriculartachycardia), Commanded, Accelerated. Therapy Analyze data and identifyepisodes the therapy that was delivered to the patient prior todetection. Valid parameters include: none, one ATP (antitachycardiapacing), more than one ATP, one shock, more than one shock, ATP andshock. Detection Analyze data and identify episodes based on averagebeats Range per minute (BPM). Valid parameters include 90 to 250.

In block 410 programmer 60 analyzes the cardiac data received fromdefibrillator 20 according to the criteria received from the user. Inone embodiment, programmer 60 dynamically builds a query based on theentered criteria and queries an internal database, thereby identifying aset of stored episodes that satisfy the user's criteria. In oneembodiment the database is maintained as a relational database. Inanother embodiment the database is maintained as one or more files on aninternal hard disk or other removable media.

In block 412 programmer 60 retrieves the cardiac data that correspondsto the identified set of episodes. In block 414 programmer 60 processesthe retrieved data and display the processed data on the interactivedisplay screen 102. In one embodiment programmer 60 displays the set ofepisodes in a chronological spread-sheet style log. In anotherembodiment programmer 60 generates and displays a graphical depiction ofthe arrhythmic episodes. In a further embodiment, colors and/or theshapes of the symbols are used to further distinguish the selectedarrhythmic events on the interactive display screen 102. The identifiedepisodes may also be printed to a strip recorder or exported to aremovable media.

Once the set of arrhythmic episodes is displayed, programmer 60 allowsthe user to enter new episode criteria. In block 414 programmer 60determines whether the user wishes to enter a new query and repeatsblocks 408, 410 and 414 if a new query is desired. If the user does notwish to enter a new query, process 400 proceeds to block 416 andterminates.

FIG. 5 illustrates display screen 102 presenting one embodiment of asummary window 502 that, according to the invention, identifies anddisplays a set of arrhythmic episodes according to episode criteriaspecified by the user. In the illustrated embodiment display screenincludes a log window 505 that displays arrhythmic episodes in aspreadsheet format. More particularly, log window 505 has displays aplurality of arrhythmic episodes on tabular format, where each rowcorresponds to an individual episode. For each episode log window 505displays various cardiac data as described in Table 1 above such as theepisode number, a date and time that the episode was detected, a type ofarrhythmia, zone of detection, beats per minute, therapy, duration, etc.

A query summary window 510 summarizes the selection criteria entered bythe user in order to determine which arrhythmic episodes are displayedin log window 505. FIG. 5, therefore, illustrates that the user haselected to show all arrhythmic episodes received from cardiacdefibrillator 20. If the user wishes to quickly and easily identify andview a subset of episodes, the user presses the modify query button 515in order to modify the selection criteria.

FIG. 6 illustrates display screen 102 presenting one embodiment of aquery input widow 605 that contains a variety of pull down windows andother input mechanisms by which a user enters criteria in order to viewa subset of the arrhythmic episodes received from cardiac defibrillator20. Using occurrence date input 610, the user instructs programmer 60 toanalyze the data and identify those episodes based on a date ofoccurrence. More specifically, the user is able to select all episodes,only those episodes that occurred since cardiac defibrillator 20 waslast reset, or episodes falling with a specified range of dates.

Via type selection 615, the user instructs programmer 60 to analyze dataand identify episodes based on episode type. In one embodiment the useris able to select all types, spontaneous arrhythmias, inducedarrhythmias, pacemaker-mediated tachycardia, atrial tachyarrhythmiaresponse, and magnet induced arrhythmias. Similarly, using zoneselection 620, a user instructs programmer 60 to analyze data andidentify episodes based on the zone of detection which can be VF(ventricular fibrillation), VT (ventricular tachycardia), VT-1(ventricular tachycardia), Commanded, Accelerated.

Rate selector 630 allows the user to analyze data and identify episodesbased on an average beat per minute (BPM) for the duration of theepisode. Valid parameters include 90 to 250 beats BPM. The userinstructs programmer 60 via therapy selection 625 to analyze data andidentify episodes according to the therapy that was delivered to thepatient prior to detection. Here, valid parameters include: none, oneATP (antitachycardia pacing), more than one ATP, one shock, more thanone shock, ATP and shock.

1. A medical device programmer communicating with an implantable medicaldevice, the programmer comprising: a user input device adapted toreceive user-specified episode criteria; electronic circuitry coupled tothe user input device, the electronic circuitry adapted to receivecardiac data representative of a plurality of arrhythmic episodes fromthe implantable medical device and analyze the cardiac data to identifya subset of the plurality of arrhythmic episodes according to theuser-specified episode criteria; and a display screen, coupled to theelectronic circuitry, to display the identified subset of the pluralityof arrhythmic episodes, the display screen including a query summarywindow configured to summarize the user-specified episode criteria. 2.The programmer of claim 1, wherein the display screen further comprisesa query input window configured to allow a user to enter theuser-specified episode criteria.
 3. The programmer of claim 2, whereinthe display screen is an interactive screen, and the user input deviceincludes the interactive screen.
 4. The programmer of claim 3, whereinthe display screen comprises a log window adapted to display theidentified subset of the plurality of arrhythmic episodes in a tabularformat.
 5. The programmer of claim 3, wherein the display screen isconfigured to display graphical depiction of the identified subset ofthe plurality of arrhythmic episodes.
 6. A medical device programmercommunicating with an implantable medical device, the programmercomprising: electronic circuitry adapted to receive cardiac datarepresentative of a plurality of arrhythmic episodes from theimplantable medical device and analyze the cardiac data to identify asubset of the plurality of arrhythmic episodes according touser-specified episode criteria; and an interactive screen coupled tothe electronic circuitry, the interactive display screen configured todisplay the identified subset of the plurality of arrhythmic episodesand including a query input window configured to receive theuser-specified episode criteria.
 7. The programmer of claim 6, whereinthe interactive screen comprises a query summary window to summarize theuser-specified episode criteria.
 8. The programmer of claim 7, whereinthe query input window comprises an occurrence date input configured toallow selection of the subset of the plurality of arrhythmic episodesbased on a specified range of dates.
 9. The programmer of claim 7,wherein the query input window comprises a type selection inputconfigured to allow selection of the subset of the plurality ofarrhythmic episodes based on an episode type.
 10. The programmer ofclaim 7, wherein the query input window comprises a zone selection inputconfigured to allow selection of the subset of the plurality ofarrhythmic episodes based on a zone of detection.
 11. The programmer ofclaim 7, wherein the query input window comprises a rate selectorconfigured to allow selection of the subset of the plurality ofarrhythmic episodes based on an average heart rate range.
 12. Theprogrammer of claim 7, wherein the query input window comprises atherapy selection input configured to allow selection of the subset ofthe plurality of arrhythmic episodes based on a therapy delivered priorto an episode of the plurality of arrhythmic episodes.
 13. A method foroperating a medical device programmer, the method comprising: receivingcardiac data representative of a plurality of arrhythmic episodes froman implantable medical device; receiving the episode criteria from auser input device; identifying a set of arrhythmic episodes from theplurality of arrhythmic episodes according to the received episodecriteria; and displaying the identified set of arrhythmic episodes onthe display screen of the medical device programmer.
 14. The method ofclaim 13, further comprising presenting episode criteria inputs on thedisplay screen.
 15. The method of claim 14, wherein presenting theepisode criteria inputs comprises presenting a plurality ofuser-modifiable data filters.
 16. The method of claim 15, whereindisplaying the identified set of arrhythmic episodes comprisesdisplaying the identified set of arrhythmic episodes in a spread-sheetformat.
 17. The method of claim 15, wherein displaying the identifiedset of arrhythmic episodes comprises displaying a graphical depiction ofthe identified set of arrhythmic episodes.
 18. The method of claim 15,further comprising displaying a summary of the plurality of arrhythmicepisodes in a spread-sheet format.